Effect of unloading strain rate on the elastic modulus of a viscoelastic solid determined by nanoindentation

被引：0

作者：

Fujisawa N. ^{[1
]}

Swain M.V. ^{[1
,2
,3
]}

机构：

[1] School of Aerospace Mechanical and Mechatronic Engineering, University of Sydney, Sydney

[2] Biomaterials Unit, Department of Oral Sciences, University of Otago, Duniden

[3] Biomaterials Science Research Unit, Faculty of Dentistry, University of Sydney, Surry Hills

来源：

Journal of Materials Research | 2006年 / 21卷 / 3期

基金：

澳大利亚研究理事会;

关键词：

D O I：

10.1557/jmr.2006.0087

中图分类号：

学科分类号：

摘要：

The elastic modulus of an amorphous polymer was investigated by nanoindentation using combinations of ten total penetration depths and three constant unload rates. This experimental design provided a range of unloading strain rates coexisting with a range of depths. The elastic modulus of the material was found to correlate strongly with the unloading strain rate, whereas its correlation with the indentation depth was statistically nonsignificant. Thus, the increase of elastic modulus that occurred with decreasing depth at each constant unload rate was merely due to the increasing unloading strain rate associated with the decreasing depth. The true depth dependence of a rate-dependent material can therefore be studied only by maintaining a constant unloading strain rate across the entire depth range. The implications of these results to the continuous stiffness measurement technique are considered. © 2006 Materials Research Society.

引用

页码：708 / 714

页数：6

共 15 条

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